Honors Projects


Objective: Current studies on vocal fry at BGSU involve categorizing various types of vocal fry production (Proctor et al., 2019 ASHA conference). The objective of the current study was to characterize vocal fry types using acoustic, airflow, and electroglottographic measures. Such characterization should shed light on the physiological production of vocal fry and potential clinical understanding and intervention.

Methods/design: Three men and three women, 18-22 years old, read the Rainbow passage as well as spoke conversationally and spontaneously in a sound treated booth. The participants spoke using a microphone and an EGG system (Kay Model 6103), as well as with and without the use of a face mask (Glottal Enterprises MSIF-2 system). The participants were asked to speak normally. There was no mention of vocal fry to them.

Results: A number of the categories of vocal fry were found in the corpus (e.g., single pulses, double pulses, multiple pulses, period doubling, delayed fry). Also the corpus included interesting results for rough voice and aperiodic segments. The figure below shows an example of period doubling. The laryngeal aspect shows a range of glottal closing and opening secondarily to the primary glottal closing and opening (the bottom EGG signal), both occurring in the period of two normal cycles (shown to the left). This example is similar to almost all others in the sense that the glottal activity typically follows the wideband airflow activity (middle trace) as well as the acoustic signal (top trace).

Conclusions: The study emphasizes the reality of the laryngeal function in the production of vocal fry, wherein the acoustic transients and various timing of glottal pulses can be seen in all three signals (acoustic, airflow, glottographic). This suggests that the primary cause of vocal fry is laryngeal, but seen and heard as sequences of transients both acoustic and aerodynamic.


Communication Sciences and Disorders


Communication Sciences and Disorders

First Advisor

Dr. Ronald Scherer

First Advisor Department

Communication Sciences and Disorders

Second Advisor

Dr. Lewis Fulcher

Second Advisor Department

Physics and Astronomy

Publication Date